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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-globaldeclarationinstantiation
es6id: 15.1.8
description: Declaration of variable where permissible
info: |
[...]
11. Let declaredVarNames be a new empty List.
12. For each d in varDeclarations, do
a. If d is a VariableDeclaration or a ForBinding, then
i. For each String vn in the BoundNames of d, do
1. If vn is not an element of declaredFunctionNames, then
a. Let vnDefinable be ? envRec.CanDeclareGlobalVar(vn).
b. If vnDefinable is false, throw a TypeError exception.
c. If vn is not an element of declaredVarNames, then
i. Append vn to declaredVarNames.
[...]
18. For each String vn in declaredVarNames, in list order do
a. Perform ? envRec.CreateGlobalVarBinding(vn, false).
[...]
8.1.1.4.15 CanDeclareGlobalVar
1. Let envRec be the global Environment Record for which the method was
invoked.
2. Let ObjRec be envRec.[[ObjectRecord]].
3. Let globalObject be the binding object for ObjRec.
4. Let hasProperty be ? HasOwnProperty(globalObject, N).
5. If hasProperty is true, return true.
6. Return ? IsExtensible(globalObject).
includes: [propertyHelper.js]
---*/
$.evalScript('var brandNew;');
assert.sameValue(
this.brandNew, undefined, 'new binding on an extensible global object'
);
verifyEnumerable(this, 'brandNew');
verifyWritable(this, 'brandNew');
verifyNotConfigurable(this, 'brandNew');
Object.defineProperty(
this,
'configurable',
{ configurable: true, writable: false, enumerable: false, value: 0 }
);
Object.defineProperty(
this,
'nonConfigurable',
{ configurable: false, writable: false, enumerable: false, value: 0 }
);
// Prevent extensions on the global object to ensure that detail is not
// considered by any of the declarations which follow.
Object.preventExtensions(this);
$.evalScript('var configurable;');
assert.sameValue(configurable, 0, 'like-named configurable property');
verifyNotEnumerable(this, 'configurable');
verifyNotWritable(this, 'configurable');
verifyConfigurable(this, 'configurable');
$.evalScript('var nonConfigurable;');
assert.sameValue(nonConfigurable, 0, 'like-named non-configurable property');
verifyNotEnumerable(this, 'nonConfigurable');
verifyNotWritable(this, 'nonConfigurable');
verifyNotConfigurable(this, 'nonConfigurable');
|
